This is a book that explores the thinking of a group of prominent philosophers who have reflected on the dimension of human experience that can be distinguished with the term moral (although also with the term ethics). The thinkers who star in these pages, whom the author exposes and with whom he also discusses from certain perspectives, are, with the exception of Emmanuel Kant, all contemporaries. What they have in common is their contribution to elucidating the problem of the rational and cognitive foundations of moral principles, concepts and judgments as prominent manifestations of moral experience. Although each of the six chapters can be read independently, the volume offers a woven sample of the diversity of approaches to morality, rationality and knowledge that this debate is capable of hosting. Its common thread is found in the overlap of the different arguments surrounding the topic in order to make them commensurable in favor of a fruitful discussion. Both with the exposition and with the discussion of the approaches raised in the book, the author's main objective is to disseminate a part of the best contemporary moral philosophy among academics and students concerned with the subject.